An investigation on the effects of bovine papillomavirus type 4 E5 protein on major histocompatibility complex class I

Transformed cells expressing BPV-1 E5 or BPV-4 E5 retain major histocompatibility class I (MHC I) molecules in the Golgi apparatus and cause the inhibition of transport of the complex to the cell surface. This effect can be ascribed to a failure of acidification of the Golgi apparatus. In addition, the total amount of both MHC I protein and mRNA is reduced in E5-transformed cells. Results from this thesis show that: a) Transcription inhibition can be alleviated by interferon treatment and the degradation of MHC I heavy chain (HC) can be reversed by treatment with inhibitors of proteasomes and lysosomes. However, the inhibition of transport of MHC I to the cell surface is irreversible. b) E5 is capable of physically interacting with heavy chain. Together with the inhibition of the vacuolar (ATPase (due to the interaction between E5 and 16k subunit c), the interaction between E5 and heavy chain is likely to be responsible for retention of MHC I in the Golgi apparatus. c) C-terminus deletion mutants of E5 are incapable of either down-regulating surface MHC class I or interacting with heavy chain, establishing that the C-terminus domain of E5 is important in the inhibition of MHC I. d) Other two PV E5 proteins, BPV-1 E5 and HPV-16 E5 are able to interact physically with heavy chains from different alleles. BPV-1 E5 interacts with two equine classical class I heavy chains (EqB2 and EqB4) in vitro and the HPV-16 E5 interacts with classical HLA-A1, A2 and B8 in vitro and with HLA-A3 in vivo. e) Like HPV-16 E5, BPV-4 E5 is incapable of down-regulating certain non-classical MHC genes. These observations lead to a deeper understanding of the general down-regulation of MHC class I by the E5 proteins. Lack of surface classical MHC class I and presence of non-classical MHC class I in infected cells expressing E5 would allow evasion of cytotoxic T lymphocyte and NK killing and thus establishment of viral infection

Reliability, Availability, Maintainability (RAM) study, on reciprocating compressors API 618

Abstract The Oil & Gas industry has continuously increased its requirements and together with the high complexity of technological systems and the higher competitiveness of markets, has compelled providers to implement adequate management strategies for these systems in order to improve their availability and productivity to meet those more demanding criteria. In this context, the complex of RAM factors constitute a strategic approach for integrating reliability, availability and maintainability, by using methods, tools and engineering techniques (Mean Time to Failure, Equipment down Time and System Availability values) to identify and quantify equipment and system failures that prevent the achievement of the productive objectives. The application of such methodologies requires a deep experience and know-how together with the possibility of acquiring and processing data in operating conditions. This paper presents the most relevant aspects and findings of a study conducted for assessing the operational performance of a reciprocating compressor system package installed and used in the oil and gas' industries. The study was based on the analysis of the behaviour of states defined for each individual parts and component of reciprocating compressor and also aimed to identify and evaluate the effects of RAM-type factors and was conducted in collaboration with a private company that, for privacy reasons, will be named RC company. The Methodologies procedures used in this descriptive study were the bibliographical research, documentary and content analysis of the main literature. Adopting the most suitable maintenance strategy is one of the main challenges that maintenance managers face. The main purpose of this work is to propose a new approach to evaluate maintenance strategies. In this study, three criteria called reliability, availability and maintainability (RAM) have been employed to compare to future maintenance strategies

Simulations and plans for possible DLA experiments at SINBAD

In this work we present the outlines of possible experiments for dielectric laser acceleration (DLA) of ultra-short relativistic electron bunches produced by the ARES linac, currently under construction at the SINBAD facility (DESY Hamburg). The experiments are to be performed as part of the Accelerator on a Chip International Program (ACHIP), funded by the Gordon and Betty Moore Foundation. At SINBAD we plan to test the acceleration of already pre-accelerated relativistic electron bunches in laser-illuminated dielectric grating structures. We present outlines of both the acceleration of ultra-short single bunches, as well as the option to accelerate phase-synchronous sub-fs microbunch trains. Here the electron bunch is conditioned prior to the injection by interaction with an external laser field in an undulator. This generates a sinusoidal energy modulation that is transformed into periodic microbunches in a subsequent chicane. The phase synchronization is achieved by driving both the modulation process and the DLA with the same laser pulse. In addition to the conceptual layouts and plans of the experiments we present start-to-end simulation results for different ARES working points.Comment: EAAC'17 conference proceeding

Mechanistic Insights into Excited State Intramolecular Proton Transfer in Isolated and Metal Chelated Supramolecular Chemosensors

Mechanistic studies of the excited state intramolecular proton transfer in a series of related and progressively more complex supramolecular chromophores.</p

experimental and numerical study of multiphase flow phenomena and models in oil gas industry

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